1. Field of the Invention
The present invention relates to a transformer, and more particularly, to a transformer having a minimized leakage inductance.
2. Description of the Related Art
Various kinds of power supplies are required in various electronic devices such as a television (TV), a monitor, a personal computer (PC), an office automation (OA) device, and the like. Therefore, these electronic devices generally include power supplies converting an alternating current (AC) power supplied from the outside into a power required for each electronic appliance.
Among power supplies, a power supply using a switching mode (for example, a switch mode power supply (SMPS)) has mainly recently been used. This SMPS basically includes a switching transformer.
The switching transformer generally converts an AC power of 85 to 265 V into a direct current (DC) power of 3 to 30 V through high frequency oscillation of 25 to 100 KHz. Therefore, the switching transformer has significantly reduced core and bobbin sizes as compared to a general transformer converting an AC power of 85 to 265 V into an AC current of 3 to 30 V through frequency oscillation of 50 to 60 Hz, and stably supplies a low voltage and low current DC power to an electronic appliance. Accordingly, the switching transformer has recently been widely used in an electronic appliance that has tended to be miniaturized.
This switching transformer needs to be designed to have a small leakage inductance in order to increase energy conversion efficiency. However, in accordance with the miniaturization of the switching transformer, it may be difficult to design a switching transformer having a small leakage inductance.